The invention relates to a method for dry cooling coke in a closed cooling chamber with as complete a recovery of the sensible heat of the glowing coke as possible, and to a coke cooler to implement the method.
A number of coke dry cooling methods are known in which the sensible coke heat is carried away in a cooling shaft by as inert a gas as possible. The inert gas is circulated and transfers the heat in a subsequent steam boiler.
A compilation of various methods operating in accordance with this principle and the equipment pertaining thereto is contained in "Gluckauf" 114 (1978) No. 14, page 611 ff.
In the course of time, significance has been gained by coke dry cooling equipment in which the hot coke is first placed in batches into a prechamber located above the actual cooling chamber. Regardless of the discharge speed of the completely cooled coke at the bottom of the prechamber, the hot coke reaches the lower cooling chamber continuously, for example, in the Gipro coke method or equipment according to West German Auslegeschrift No. 2 432 025 and West German Auslegeschrift No. 1 471 589. At irregular coke input, such as due to transport malfunctions, the cooling of the coke and particularly the steam generation associated with it can be kept constant for a certain period of time by means of the prechamber. In this method, the coke is cooled exclusively by direct heat exchange with an inert circulating gas which is blown in counterflow heat transfer relationship through the coke fill and subsequently re-transmits the heat absorbed to other media directly or indirectly. This type of cooling requires that great amounts of cooling gas be blown and circulated through the coke fill. The high cooling gas velocities at the upper outer end of the cooling chamber especially lead to the necessity in the known cooling equipment arrangements of having to separate as best as possible considerable amounts of coke dust to avoid excessive wear and fouling of the lines and equipment.
West German Auslegeschrift No. 1 471 589 discloses that the gas outlet between prechamber and cooling tank consists of channels distributed over the entire periphery of the chamber and directed obliquely upwards and, at a higher level, of a circular line encircling the prechamber, in which circular line said channels end.
After leaving the coke fill, the gas is conducted into the circular line immediately at high velocity through only a few small masonry channels. It is not practically possible to clean these channels.
In addition to these new methods and equipment for dry cooling coke, with direct heat exchange between coke and circulating gas, West German Pat. No. 601 392 discloses equipment for the dry cooling of coke in a closed chamber surrounded by coolant water lines. The coolant water lines are fed from below through distributor pipes and a tank while on top they communicate with the atmosphere through a pipe, the outlet of which is disposed over a drain chute. This method according to West German Pat. No. 601 392 has the disadvantage that the coke can be cooled in the cooling chamber only in batches, and not continuously, and that cooling usually takes three to four hours. Therefore, this method requires a multiplicity of cooling tanks per battery.